DISSERTATION RESEARCH: Maternal effects of stress in a plural-breeding rodent

Tufts University, Medford MA

Investigators

Abstract

The quality of parental care influences offspring fitness. In domesticated laboratory rodents, pups that have chronically stressed mothers receive low quality care, leading pups to develop highly reactive stress responses. Affected pups will have high stress hormone levels as adults, which can have severe consequences on their future survival and reproductive output. This research examines the relationship between stressed mothers, poor maternal care, and the offspring stress response and survival in the degu (Octodon degus), a wild, free-living rodent. Degus practice a unique reproductive tactic called "plural breeding with communal care" where multiple mothers cooperate to raise each other's pups. This research also will ask whether this unique social strategy can buffer the offspring against post-natal stress. By manipulating the stress levels of mothers and measuring stress hormone levels in pups in both field and laboratory experiments, this research will provide a comprehensive description of the links between stress, development, and, ultimately, survival. This link has never been demonstrated in a wild, free-living rodent. This research will have broader impacts because it will address the link between parental care and offspring survival, which is a major unsolved problem in ecology and stress physiology. Further broader impacts of this research will include scientific outreach through a weekly blog that is incorporated into the curriculum of an undergraduate course, presentations to senior citizens and middle/high school girls, undergraduate research opportunities, and support for a young scientist completing her PhD research.